Cygnus ready to spread its wings, fly to ISS

The International Space Station is preparing to welcome a Cygnus resupply vessel to the commercial spaceflight party.

Orbital Sciences Corporation

ORB-D1 Mission Patch

Because it's not a real mission without a patch.

On Wednesday morning, Orbital Sciences Corporation’s Antares rocket is slated to lift off from NASA's Wallops Flight Facility on the Virginia coast. It will be the second flight of Antares, which successfully sailed a test payload into orbit last April. Cygnus is carrying carrying 1,300 pounds (589 kilograms) of food, clothing and other cargo for its maiden voyage—a demonstration mission to prove its capabilities.

Wednesday's launch window is a relatively short fifteen minutes, from 10:50 to 11:05 a.m. EDT (14:50 to 15:05 UTC). Although the launch was delayed from Tuesday to Wednesday due to bad weather and a flaky data cable, Cygnus is still expected to arrive at the station on Sunday, Sept. 22, with capture scheduled for 7:17 a.m. Like SpaceX’s Dragon, Cygnus will be berthed to the station's Harmony node using Canadarm. NASA says the vehicle is expected to be installed around 9 a.m.

Here is your Antares ascent timeline:

Event

Altitude (kilometers)

Elapsed time (mm:ss)

Stage one ignition

0

00:00

Liftoff

0

00:02

Main Engine Cutoff (MECO)

107

03:53

Stage one separation

113

03:58

Fairing separation

182

05:20

Interstage separation

184

05:25

Stage 2 ignition

187

05:29

Stage 2 burnout / orbit insertion

250

08:02

Cygnus separation

249

10:02

Orbital Sciences Corporation

Antares ORB-D1 Ready for Launch

Orbital Sciences Corporation's Antares rocket and Cygnus resupply spacecraft stand on the launchpad prior to their Sept. 18 launch to the International Space Station.

Cygnus will be controlled from Orbital's Mission Control Center in Dulles, Va. The spacecraft's initial orbit will be 245 x 300 kilometers. Over the next few days, Cygnus will conduct a series of orbit-raising thruster burns to position itself four kilometers beneath the station. In between those burns, it will perform its first three demonstration tasks: Absolute GPS (Demo 1), Free drift (Demo 2a) and abort (Demo 2b).

When Cygnus arrives at the four kilometer point, joint operations between Orbital and NASA's Mission Control Center in Houston begin. Here are the joint operations events:

Event

Description

Range

Demo 3

Relative GPS navigation demonstration

4 km

Demo 4

Onboard targeting demonstration

4 km

Thruster burn

Close on station

4 km to 1.4 km

Demo 5

Autonomous maneuver demonstration

4 km to 1.4 km

Thruster burn

Close on station

4 km to 1.4 km

Demo 6

Hardware Command Panel (HCP) checkout

1.4 km

Thruster burns

Intercept R-bar, hold autonomously at 250 m

1.4 km to 250 m

Demo 7

LIDAR navigation demonstration

250 m

Thruster burn

Close on station

250 m to 230 m

Demo 8

HCP retreat demonstration

230 m

Thruster burn

Retreat from station

230 m to 250 m

Thruster burn

Close on station

250 m to 230 m

Demo 9

HCP hold demonstration

230 m

Thruster burn

Close on station

250 m to 30 m

Enter Keep-Out Sphere

Close on station

200 m

Demo 10

LIDAR JEM-A reflector tracking demonstration

200 m to 30m

Hold for final approach

Hold for final approach

30 m

Thruster burn

Final approach

30 m to 12 m

Hold for capture

Hold for capture

12 m

Capture

Capture with Canadarm by Karen Nyberg and Luca Parmitano

12 m

Orbital Sciences Corporation

Cygnus ISS Approach Profile

As Cygnus approaches the station, it will conduct a series of demonstration maneuvers designed to prove various spacecraft capabilities.